<?php

/**
 * @file
 * The theme system, which controls the output of Drupal.
 *
 * The theme system allows for nearly all output of the Drupal system to be
 * customized by user themes.
 */

/**
 * @defgroup content_flags Content markers
 * @{
 * Markers used by theme_mark() and node_mark() to designate content.
 * @see theme_mark(), node_mark()
 */

/**
 * Mark content as read.
 */
define('MARK_READ', 0);

/**
 * Mark content as being new.
 */
define('MARK_NEW', 1);

/**
 * Mark content as being updated.
 */
define('MARK_UPDATED', 2);

/**
 * @} End of "Content markers".
 */

/**
 * Determines if a theme is available to use.
 *
 * @param $theme
 *   Either the name of a theme or a full theme object.
 *
 * @return
 *   Boolean TRUE if the theme is enabled or is the site administration theme;
 *   FALSE otherwise.
 */
function drupal_theme_access($theme) {
	if (is_object($theme)) {
		return _drupal_theme_access($theme);
	}
	else {
		$themes = list_themes();
		return isset($themes[$theme]) && _drupal_theme_access($themes[$theme]);
	}
}

/**
 * Helper function for determining access to a theme.
 *
 * @see drupal_theme_access()
 */
function _drupal_theme_access($theme) {
	$admin_theme = variable_get('admin_theme');
	return !empty($theme->status) || ($admin_theme && $theme->name == $admin_theme);
}

/**
 * Initialize the theme system by loading the theme.
 */
function drupal_theme_initialize() {
	global $theme, $user, $theme_key;

	// If $theme is already set, assume the others are set, too, and do nothing
	if (isset($theme)) {
		return;
	}

	drupal_bootstrap(DRUPAL_BOOTSTRAP_DATABASE);
	$themes = list_themes();

	// Only select the user selected theme if it is available in the
	// list of themes that can be accessed.
	$theme = !empty($user->theme) && drupal_theme_access($user->theme) ? $user->theme : variable_get('theme_default', 'bartik');

	// Allow modules to override the theme. Validation has already been performed
	// inside menu_get_custom_theme(), so we do not need to check it again here.
	$custom_theme = menu_get_custom_theme();
	$theme = !empty($custom_theme) ? $custom_theme : $theme;

	// Store the identifier for retrieving theme settings with.
	$theme_key = $theme;

	// Find all our ancestor themes and put them in an array.
	$base_theme = array();
	$ancestor = $theme;
	while ($ancestor && isset($themes[$ancestor]->base_theme)) {
		$ancestor = $themes[$ancestor]->base_theme;
		$base_theme[] = $themes[$ancestor];
	}
	_drupal_theme_initialize($themes[$theme], array_reverse($base_theme));

	// Themes can have alter functions, so reset the drupal_alter() cache.
	drupal_static_reset('drupal_alter');

	// Provide the page with information about the theme that's used, so that a
	// later Ajax request can be rendered using the same theme.
	// @see ajax_base_page_theme()
	$setting['ajaxPageState'] = array(
			'theme' => $theme_key,
			'theme_token' => drupal_get_token($theme_key),
	);
	drupal_add_js($setting, 'setting');
}

/**
 * Initialize the theme system given already loaded information. This
 * function is useful to initialize a theme when no database is present.
 *
 * @param $theme
 *   An object with the following information:
 *     filename
 *       The .info file for this theme. The 'path' to
 *       the theme will be in this file's directory. (Required)
 *     owner
 *       The path to the .theme file or the .engine file to load for
 *       the theme. (Required)
 *     stylesheet
 *       The primary stylesheet for the theme. (Optional)
 *     engine
 *       The name of theme engine to use. (Optional)
 * @param $base_theme
 *    An optional array of objects that represent the 'base theme' if the
 *    theme is meant to be derivative of another theme. It requires
 *    the same information as the $theme object. It should be in
 *    'oldest first' order, meaning the top level of the chain will
 *    be first.
 * @param $registry_callback
 *   The callback to invoke to set the theme registry.
 */
function _drupal_theme_initialize($theme, $base_theme = array(), $registry_callback = '_theme_load_registry') {
	global $theme_info, $base_theme_info, $theme_engine, $theme_path;
	$theme_info = $theme;
	$base_theme_info = $base_theme;

	$theme_path = dirname($theme->filename);

	// Prepare stylesheets from this theme as well as all ancestor themes.
	// We work it this way so that we can have child themes override parent
	// theme stylesheets easily.
	$final_stylesheets = array();

	// Grab stylesheets from base theme
	foreach ($base_theme as $base) {
		if (!empty($base->stylesheets)) {
			foreach ($base->stylesheets as $media => $stylesheets) {
				foreach ($stylesheets as $name => $stylesheet) {
					$final_stylesheets[$media][$name] = $stylesheet;
				}
			}
		}
	}

	// Add stylesheets used by this theme.
	if (!empty($theme->stylesheets)) {
		foreach ($theme->stylesheets as $media => $stylesheets) {
			foreach ($stylesheets as $name => $stylesheet) {
				$final_stylesheets[$media][$name] = $stylesheet;
			}
		}
	}

	// And now add the stylesheets properly
	foreach ($final_stylesheets as $media => $stylesheets) {
		foreach ($stylesheets as $stylesheet) {
			drupal_add_css($stylesheet, array('group' => CSS_THEME, 'every_page' => TRUE, 'media' => $media));
		}
	}

	// Do basically the same as the above for scripts
	$final_scripts = array();

	// Grab scripts from base theme
	foreach ($base_theme as $base) {
		if (!empty($base->scripts)) {
			foreach ($base->scripts as $name => $script) {
				$final_scripts[$name] = $script;
			}
		}
	}

	// Add scripts used by this theme.
	if (!empty($theme->scripts)) {
		foreach ($theme->scripts as $name => $script) {
			$final_scripts[$name] = $script;
		}
	}

	// Add scripts used by this theme.
	foreach ($final_scripts as $script) {
		drupal_add_js($script, array('group' => JS_THEME, 'every_page' => TRUE));
	}

	$theme_engine = NULL;

	// Initialize the theme.
	if (isset($theme->engine)) {
		// Include the engine.
		include_once DRUPAL_ROOT . '/' . $theme->owner;

		$theme_engine = $theme->engine;
		if (function_exists($theme_engine . '_init')) {
			foreach ($base_theme as $base) {
				call_user_func($theme_engine . '_init', $base);
			}
			call_user_func($theme_engine . '_init', $theme);
		}
	}
	else {
		// include non-engine theme files
		foreach ($base_theme as $base) {
			// Include the theme file or the engine.
			if (!empty($base->owner)) {
				include_once DRUPAL_ROOT . '/' . $base->owner;
			}
		}
		// and our theme gets one too.
		if (!empty($theme->owner)) {
			include_once DRUPAL_ROOT . '/' . $theme->owner;
		}
	}

	if (isset($registry_callback)) {
		_theme_registry_callback($registry_callback, array($theme, $base_theme, $theme_engine));
	}
}

/**
 * Get the theme registry.
 *
 * @param $complete
 *   Optional boolean to indicate whether to return the complete theme registry
 *   array or an instance of the ThemeRegistry class. If TRUE, the complete
 *   theme registry array will be returned. This is useful if you want to
 *   foreach over the whole registry, use array_* functions or inspect it in a
 *   debugger. If FALSE, an instance of the ThemeRegistry class will be
 *   returned, this provides an ArrayObject which allows it to be accessed
 *   with array syntax and  isset(), and should be more lightweight
 *   than the full registry. Defaults to TRUE.
 *
 * @return
 *   The complete theme registry array, or an instance of the ThemeRegistry
 *   class.
 */
function theme_get_registry($complete = TRUE) {
	static $theme_registry = array();
	$key = (int) $complete;

	if (!isset($theme_registry[$key])) {
		list($callback, $arguments) = _theme_registry_callback();
		if (!$complete) {
			$arguments[] = FALSE;
		}
		$theme_registry[$key] = call_user_func_array($callback, $arguments);
	}

	return $theme_registry[$key];
}

/**
 * Set the callback that will be used by theme_get_registry() to fetch the registry.
 *
 * @param $callback
 *   The name of the callback function.
 * @param $arguments
 *   The arguments to pass to the function.
 */
function _theme_registry_callback($callback = NULL, array $arguments = array()) {
	static $stored;
	if (isset($callback)) {
		$stored = array($callback, $arguments);
	}
	return $stored;
}

/**
 * Get the theme_registry cache; if it doesn't exist, build it.
 *
 * @param $theme
 *   The loaded $theme object as returned by list_themes().
 * @param $base_theme
 *   An array of loaded $theme objects representing the ancestor themes in
 *   oldest first order.
 * @param $theme_engine
 *   The name of the theme engine.
 * @param $complete
 *   Whether to load the complete theme registry or an instance of the
 *   ThemeRegistry class.
 *
 * @return
 *   The theme registry array, or an instance of the ThemeRegistry class.
 */
function _theme_load_registry($theme, $base_theme = NULL, $theme_engine = NULL, $complete = TRUE) {
	if ($complete) {
		// Check the theme registry cache; if it exists, use it.
		$cached = cache_get("theme_registry:$theme->name");
		if (isset($cached->data)) {
			$registry = $cached->data;
		}
		else {
			// If not, build one and cache it.
			$registry = _theme_build_registry($theme, $base_theme, $theme_engine);
			// Only persist this registry if all modules are loaded. This assures a
			// complete set of theme hooks.
			if (module_load_all(NULL)) {
				_theme_save_registry($theme, $registry);
			}
		}
		return $registry;
	}
	else {
		return new ThemeRegistry('theme_registry:runtime:' . $theme->name, 'cache');
	}
}

/**
 * Write the theme_registry cache into the database.
 */
function _theme_save_registry($theme, $registry) {
	cache_set("theme_registry:$theme->name", $registry);
}

/**
 * Force the system to rebuild the theme registry; this should be called
 * when modules are added to the system, or when a dynamic system needs
 * to add more theme hooks.
 */
function drupal_theme_rebuild() {
	cache_clear_all('theme_registry', 'cache', TRUE);
}

/**
 * Builds the run-time theme registry.
 *
 * Extends DrupalCacheArray to allow the theme registry to be accessed as a
 * complete registry, while internally caching only the parts of the registry
 * that are actually in use on the site. On cache misses the complete
 * theme registry is loaded and used to update the run-time cache.
 */
class ThemeRegistry Extends DrupalCacheArray {

	/**
	 * Whether the partial registry can be persisted to the cache.
	 *
	 * This is only allowed if all modules and the request method is GET. theme()
	 * should be very rarely called on POST requests and this avoids polluting
	 * the runtime cache.
	 */
	protected $persistable;

	/**
	 * The complete theme registry array.
	 */
	protected $completeRegistry;

	function __construct($cid, $bin) {
		$this->cid = $cid;
		$this->bin = $bin;
		$this->persistable = module_load_all(NULL) && $_SERVER['REQUEST_METHOD'] == 'GET';

		$data = array();
		if ($this->persistable && $cached = cache_get($this->cid, $this->bin)) {
			$data = $cached->data;
		}
		else {
			// If there is no runtime cache stored, fetch the full theme registry,
			// but then initialize each value to NULL. This allows offsetExists()
			// to function correctly on non-registered theme hooks without triggering
			// a call to resolveCacheMiss().
			$data = $this->initializeRegistry();
			if ($this->persistable) {
				$this->set($data);
			}
		}
		$this->storage = $data;
	}

	/**
	 * Initializes the full theme registry.
	 *
	 * @return
	 *   An array with the keys of the full theme registry, but the values
	 *   initialized to NULL.
	 */
	function initializeRegistry() {
		$this->completeRegistry = theme_get_registry();

		return array_fill_keys(array_keys($this->completeRegistry), NULL);
	}

	public function offsetExists($offset) {
		// Since the theme registry allows for theme hooks to be requested that
		// are not registered, just check the existence of the key in the registry.
		// Use array_key_exists() here since a NULL value indicates that the theme
		// hook exists but has not yet been requested.
		return array_key_exists($offset, $this->storage);
	}

	public function offsetGet($offset) {
		// If the offset is set but empty, it is a registered theme hook that has
		// not yet been requested. Offsets that do not exist at all were not
		// registered in hook_theme().
		if (isset($this->storage[$offset])) {
			return $this->storage[$offset];
		}
		elseif (array_key_exists($offset, $this->storage)) {
			return $this->resolveCacheMiss($offset);
		}
	}

	public function resolveCacheMiss($offset) {
		if (!isset($this->completeRegistry)) {
			$this->completeRegistry = theme_get_registry();
		}
		$this->storage[$offset] = $this->completeRegistry[$offset];
		if ($this->persistable) {
			$this->persist($offset);
		}
		return $this->storage[$offset];
	}

	public function set($data, $lock = TRUE) {
		$lock_name = $this->cid . ':' . $this->bin;
		if (!$lock || lock_acquire($lock_name)) {
			if ($cached = cache_get($this->cid, $this->bin)) {
				// Use array merge instead of union so that filled in values in $data
				// overwrite empty values in the current cache.
				$data = array_merge($cached->data, $data);
			}
			else {
				$registry = $this->initializeRegistry();
				$data = array_merge($registry, $data);
			}
			cache_set($this->cid, $data, $this->bin);
			if ($lock) {
				lock_release($lock_name);
			}
		}
	}
}

/**
 * Process a single implementation of hook_theme().
 *
 * @param $cache
 *   The theme registry that will eventually be cached; It is an associative
 *   array keyed by theme hooks, whose values are associative arrays describing
 *   the hook:
 *   - 'type': The passed-in $type.
 *   - 'theme path': The passed-in $path.
 *   - 'function': The name of the function generating output for this theme
 *     hook. Either defined explicitly in hook_theme() or, if neither 'function'
 *     nor 'template' is defined, then the default theme function name is used.
 *     The default theme function name is the theme hook prefixed by either
 *     'theme_' for modules or '$name_' for everything else. If 'function' is
 *     defined, 'template' is not used.
 *   - 'template': The filename of the template generating output for this
 *     theme hook. The template is in the directory defined by the 'path' key of
 *     hook_theme() or defaults to $path.
 *   - 'variables': The variables for this theme hook as defined in
 *     hook_theme(). If there is more than one implementation and 'variables' is
 *     not specified in a later one, then the previous definition is kept.
 *   - 'render element': The renderable element for this theme hook as defined
 *     in hook_theme(). If there is more than one implementation and
 *     'render element' is not specified in a later one, then the previous
 *     definition is kept.
 *   - 'preprocess functions': See theme() for detailed documentation.
 *   - 'process functions': See theme() for detailed documentation.
 * @param $name
 *   The name of the module, theme engine, base theme engine, theme or base
 *   theme implementing hook_theme().
 * @param $type
 *   One of 'module', 'theme_engine', 'base_theme_engine', 'theme', or
 *   'base_theme'. Unlike regular hooks that can only be implemented by modules,
 *   each of these can implement hook_theme(). _theme_process_registry() is
 *   called in aforementioned order and new entries override older ones. For
 *   example, if a theme hook is both defined by a module and a theme, then the
 *   definition in the theme will be used.
 * @param $theme
 *   The loaded $theme object as returned from list_themes().
 * @param $path
 *   The directory where $name is. For example, modules/system or
 *   themes/bartik.
 *
 * @see theme()
 * @see _theme_process_registry()
 * @see hook_theme()
 * @see list_themes()
 */
function _theme_process_registry(&$cache, $name, $type, $theme, $path) {
	$result = array();

	// Processor functions work in two distinct phases with the process
	// functions always being executed after the preprocess functions.
	$variable_process_phases = array(
			'preprocess functions' => 'preprocess',
			'process functions'    => 'process',
	);

	$hook_defaults = array(
			'variables' => TRUE,
			'render element' => TRUE,
			'pattern' => TRUE,
			'base hook' => TRUE,
	);

	// Invoke the hook_theme() implementation, process what is returned, and
	// merge it into $cache.
	$function = $name . '_theme';
	if (function_exists($function)) {
		$result = $function($cache, $type, $theme, $path);
		foreach ($result as $hook => $info) {
			// When a theme or engine overrides a module's theme function
			// $result[$hook] will only contain key/value pairs for information being
			// overridden.  Pull the rest of the information from what was defined by
			// an earlier hook.

			// Fill in the type and path of the module, theme, or engine that
			// implements this theme function.
			$result[$hook]['type'] = $type;
			$result[$hook]['theme path'] = $path;

			// If function and file are omitted, default to standard naming
			// conventions.
			if (!isset($info['template']) && !isset($info['function'])) {
				$result[$hook]['function'] = ($type == 'module' ? 'theme_' : $name . '_') . $hook;
			}

			if (isset($cache[$hook]['includes'])) {
				$result[$hook]['includes'] = $cache[$hook]['includes'];
			}

			// If the theme implementation defines a file, then also use the path
			// that it defined. Otherwise use the default path. This allows
			// system.module to declare theme functions on behalf of core .include
			// files.
			if (isset($info['file'])) {
				$include_file = isset($info['path']) ? $info['path'] : $path;
				$include_file .= '/' . $info['file'];
				include_once DRUPAL_ROOT . '/' . $include_file;
				$result[$hook]['includes'][] = $include_file;
			}

			// If the default keys are not set, use the default values registered
			// by the module.
			if (isset($cache[$hook])) {
				$result[$hook] += array_intersect_key($cache[$hook], $hook_defaults);
			}

			// The following apply only to theming hooks implemented as templates.
			if (isset($info['template'])) {
				// Prepend the current theming path when none is set.
				if (!isset($info['path'])) {
					$result[$hook]['template'] = $path . '/' . $info['template'];
				}
			}

			// Allow variable processors for all theming hooks, whether the hook is
			// implemented as a template or as a function.
			foreach ($variable_process_phases as $phase_key => $phase) {
				// Check for existing variable processors. Ensure arrayness.
				if (!isset($info[$phase_key]) || !is_array($info[$phase_key])) {
					$info[$phase_key] = array();
					$prefixes = array();
					if ($type == 'module') {
						// Default variable processor prefix.
						$prefixes[] = 'template';
						// Add all modules so they can intervene with their own variable
						// processors. This allows them to provide variable processors even
						// if they are not the owner of the current hook.
						$prefixes += module_list();
					}
					elseif ($type == 'theme_engine' || $type == 'base_theme_engine') {
						// Theme engines get an extra set that come before the normally
						// named variable processors.
						$prefixes[] = $name . '_engine';
						// The theme engine registers on behalf of the theme using the
						// theme's name.
						$prefixes[] = $theme;
					}
					else {
						// This applies when the theme manually registers their own variable
						// processors.
						$prefixes[] = $name;
					}
					foreach ($prefixes as $prefix) {
						// Only use non-hook-specific variable processors for theming hooks
						// implemented as templates. See theme().
						if (isset($info['template']) && function_exists($prefix . '_' . $phase)) {
							$info[$phase_key][] = $prefix . '_' . $phase;
						}
						if (function_exists($prefix . '_' . $phase . '_' . $hook)) {
							$info[$phase_key][] = $prefix . '_' . $phase . '_' . $hook;
						}
					}
				}
				// Check for the override flag and prevent the cached variable
				// processors from being used. This allows themes or theme engines to
				// remove variable processors set earlier in the registry build.
				if (!empty($info['override ' . $phase_key])) {
					// Flag not needed inside the registry.
					unset($result[$hook]['override ' . $phase_key]);
				}
				elseif (isset($cache[$hook][$phase_key]) && is_array($cache[$hook][$phase_key])) {
					$info[$phase_key] = array_merge($cache[$hook][$phase_key], $info[$phase_key]);
				}
				$result[$hook][$phase_key] = $info[$phase_key];
			}
		}

		// Merge the newly created theme hooks into the existing cache.
		$cache = $result + $cache;
	}

	// Let themes have variable processors even if they didn't register a template.
	if ($type == 'theme' || $type == 'base_theme') {
		foreach ($cache as $hook => $info) {
			// Check only if not registered by the theme or engine.
			if (empty($result[$hook])) {
				foreach ($variable_process_phases as $phase_key => $phase) {
					if (!isset($info[$phase_key])) {
						$cache[$hook][$phase_key] = array();
					}
					// Only use non-hook-specific variable processors for theming hooks
					// implemented as templates. See theme().
					if (isset($info['template']) && function_exists($name . '_' . $phase)) {
						$cache[$hook][$phase_key][] = $name . '_' . $phase;
					}
					if (function_exists($name . '_' . $phase . '_' . $hook)) {
						$cache[$hook][$phase_key][] = $name . '_' . $phase . '_' . $hook;
						$cache[$hook]['theme path'] = $path;
					}
					// Ensure uniqueness.
					$cache[$hook][$phase_key] = array_unique($cache[$hook][$phase_key]);
				}
			}
		}
	}
}

/**
 * Build the theme registry cache.
 *
 * @param $theme
 *   The loaded $theme object as returned by list_themes().
 * @param $base_theme
 *   An array of loaded $theme objects representing the ancestor themes in
 *   oldest first order.
 * @param $theme_engine
 *   The name of the theme engine.
 */
function _theme_build_registry($theme, $base_theme, $theme_engine) {
	$cache = array();
	// First, process the theme hooks advertised by modules. This will
	// serve as the basic registry. Since the list of enabled modules is the same
	// regardless of the theme used, this is cached in its own entry to save
	// building it for every theme.
	if ($cached = cache_get('theme_registry:build:modules')) {
		$cache = $cached->data;
	}
	else {
		foreach (module_implements('theme') as $module) {
			_theme_process_registry($cache, $module, 'module', $module, drupal_get_path('module', $module));
		}
		// Only cache this registry if all modules are loaded.
		if (module_load_all(NULL)) {
			cache_set('theme_registry:build:modules', $cache);
		}
	}

	// Process each base theme.
	foreach ($base_theme as $base) {
		// If the base theme uses a theme engine, process its hooks.
		$base_path = dirname($base->filename);
		if ($theme_engine) {
			_theme_process_registry($cache, $theme_engine, 'base_theme_engine', $base->name, $base_path);
		}
		_theme_process_registry($cache, $base->name, 'base_theme', $base->name, $base_path);
	}

	// And then the same thing, but for the theme.
	if ($theme_engine) {
		_theme_process_registry($cache, $theme_engine, 'theme_engine', $theme->name, dirname($theme->filename));
	}

	// Finally, hooks provided by the theme itself.
	_theme_process_registry($cache, $theme->name, 'theme', $theme->name, dirname($theme->filename));

	// Let modules alter the registry.
	drupal_alter('theme_registry', $cache);

	// Optimize the registry to not have empty arrays for functions.
	foreach ($cache as $hook => $info) {
		foreach (array('preprocess functions', 'process functions') as $phase) {
			if (empty($info[$phase])) {
				unset($cache[$hook][$phase]);
			}
		}
	}
	return $cache;
}

/**
 * Return a list of all currently available themes.
 *
 * Retrieved from the database, if available and the site is not in maintenance
 * mode; otherwise compiled freshly from the filesystem.
 *
 * @param $refresh
 *   Whether to reload the list of themes from the database. Defaults to FALSE.
 *
 * @return
 *   An associative array of the currently available themes. The keys are the
 *   names of the themes and the values are objects having the following
 *   properties:
 *   - 'filename': The name of the .info file.
 *   - 'name': The name of the theme.
 *   - 'status': 1 for enabled, 0 for disabled themes.
 *   - 'info': The contents of the .info file.
 *   - 'stylesheets': A two dimensional array, using the first key for the
 *     'media' attribute (e.g. 'all'), the second for the name of the file
 *     (e.g. style.css). The value is a complete filepath
 *     (e.g. themes/bartik/style.css).
 *   - 'scripts': An associative array of JavaScripts, using the filename as key
 *     and the complete filepath as value.
 *   - 'engine': The name of the theme engine.
 *   - 'base theme': The name of the base theme.
 */
function list_themes($refresh = FALSE) {
	$list = &drupal_static(__FUNCTION__, array());

	if ($refresh) {
		$list = array();
		system_list_reset();
	}

	if (empty($list)) {
		$list = array();
		$themes = array();
		// Extract from the database only when it is available.
		// Also check that the site is not in the middle of an install or update.
		if (!defined('MAINTENANCE_MODE')) {
			try {
				$themes = system_list('theme');
			}
			catch (Exception $e) {
				// If the database is not available, rebuild the theme data.
				$themes = _system_rebuild_theme_data();
			}
		}
		else {
			// Scan the installation when the database should not be read.
			$themes = _system_rebuild_theme_data();
		}

		foreach ($themes as $theme) {
			foreach ($theme->info['stylesheets'] as $media => $stylesheets) {
				foreach ($stylesheets as $stylesheet => $path) {
					$theme->stylesheets[$media][$stylesheet] = $path;
				}
			}
			foreach ($theme->info['scripts'] as $script => $path) {
				$theme->scripts[$script] = $path;
			}
			if (isset($theme->info['engine'])) {
				$theme->engine = $theme->info['engine'];
			}
			if (isset($theme->info['base theme'])) {
				$theme->base_theme = $theme->info['base theme'];
			}
			// Status is normally retrieved from the database. Add zero values when
			// read from the installation directory to prevent notices.
			if (!isset($theme->status)) {
				$theme->status = 0;
			}
			$list[$theme->name] = $theme;
		}
	}

	return $list;
}

/**
 * Generates themed output.
 *
 * All requests for themed output must go through this function. It examines
 * the request and routes it to the appropriate
 * @link themeable theme function or template @endlink, by checking the theme
 * registry.
 *
 * The first argument to this function is the name of the theme hook. For
 * instance, to theme a table, the theme hook name is 'table'. By default, this
 * theme hook could be implemented by a function called 'theme_table' or a
 * template file called 'table.tpl.php', but hook_theme() can override the
 * default function or template name.
 *
 * If the implementation is a template file, several functions are called
 * before the template file is invoked, to modify the $variables array. These
 * fall into the "preprocessing" phase and the "processing" phase, and are
 * executed (if they exist), in the following order (note that in the following
 * list, HOOK indicates the theme hook name, MODULE indicates a module name,
 * THEME indicates a theme name, and ENGINE indicates a theme engine name):
 * - template_preprocess(&$variables, $hook): Creates a default set of variables
 *   for all theme hooks.
 * - template_preprocess_HOOK(&$variables): Should be implemented by
 *   the module that registers the theme hook, to set up default variables.
 * - MODULE_preprocess(&$variables, $hook): hook_preprocess() is invoked on all
 *   implementing modules.
 * - MODULE_preprocess_HOOK(&$variables): hook_preprocess_HOOK() is invoked on
 *   all implementing modules, so that modules that didn't define the theme hook
 *   can alter the variables.
 * - ENGINE_engine_preprocess(&$variables, $hook): Allows the theme engine to
 *   set necessary variables for all theme hooks.
 * - ENGINE_engine_preprocess_HOOK(&$variables): Allows the theme engine to set
 *   necessary variables for the particular theme hook.
 * - THEME_preprocess(&$variables, $hook): Allows the theme to set necessary
 *   variables for all theme hooks.
 * - THEME_preprocess_HOOK(&$variables): Allows the theme to set necessary
 *   variables specific to the particular theme hook.
 * - template_process(&$variables, $hook): Creates a default set of variables
 *   for all theme hooks.
 * - template_process_HOOK(&$variables): This is the first processor specific
 *   to the theme hook; it should be implemented by the module that registers
 *   it.
 * - MODULE_process(&$variables, $hook): hook_process() is invoked on all
 *   implementing modules.
 * - MODULE_process_HOOK(&$variables): hook_process_HOOK() is invoked on
 *   on all implementing modules, so that modules that didn't define the theme
 *   hook can alter the variables.
 * - ENGINE_engine_process(&$variables, $hook): Allows the theme engine to set
 *   necessary variables for all theme hooks.
 * - ENGINE_engine_process_HOOK(&$variables): Allows the theme engine to set
 *   necessary variables for the particular theme hook.
 * - ENGINE_process(&$variables, $hook): Allows the theme engine to process the
 *   variables.
 * - ENGINE_process_HOOK(&$variables): Allows the theme engine to process the
 *   variables specific to the theme hook.
 * - THEME_process(&$variables, $hook):  Allows the theme to process the
 *   variables.
 * - THEME_process_HOOK(&$variables):  Allows the theme to process the
 *   variables specific to the theme hook.
 *
 * If the implementation is a function, only the theme-hook-specific preprocess
 * and process functions (the ones ending in _HOOK) are called from the
 * list above. This is because theme hooks with function implementations
 * need to be fast, and calling the non-theme-hook-specific preprocess and
 * process functions for them would incur a noticeable performance penalty.
 *
 * There are two special variables that these preprocess and process functions
 * can set: 'theme_hook_suggestion' and 'theme_hook_suggestions'. These will be
 * merged together to form a list of 'suggested' alternate theme hooks to use,
 * in reverse order of priority. theme_hook_suggestion will always be a higher
 * priority than items in theme_hook_suggestions. theme() will use the
 * highest priority implementation that exists. If none exists, theme() will
 * use the implementation for the theme hook it was called with. These
 * suggestions are similar to and are used for similar reasons as calling
 * theme() with an array as the $hook parameter (see below). The difference
 * is whether the suggestions are determined by the code that calls theme() or
 * by a preprocess or process function.
 *
 * @param $hook
 *   The name of the theme hook to call. If the name contains a
 *   double-underscore ('__') and there isn't an implementation for the full
 *   name, the part before the '__' is checked. This allows a fallback to a more
 *   generic implementation. For example, if theme('links__node', ...) is
 *   called, but there is no implementation of that theme hook, then the 'links'
 *   implementation is used. This process is iterative, so if
 *   theme('links__contextual__node', ...) is called, theme() checks for the
 *   following implementations, and uses the first one that exists:
 *   - links__contextual__node
 *   - links__contextual
 *   - links
 *   This allows themes to create specific theme implementations for named
 *   objects and contexts of otherwise generic theme hooks. The $hook parameter
 *   may also be an array, in which case the first theme hook that has an
 *   implementation is used. This allows for the code that calls theme() to
 *   explicitly specify the fallback order in a situation where using the '__'
 *   convention is not desired or is insufficient.
 * @param $variables
 *   An associative array of variables to merge with defaults from the theme
 *   registry, pass to preprocess and process functions for modification, and
 *   finally, pass to the function or template implementing the theme hook.
 *   Alternatively, this can be a renderable array, in which case, its
 *   properties are mapped to variables expected by the theme hook
 *   implementations.
 *
 * @return
 *   An HTML string representing the themed output.
 *
 * @see themeable
 */
function theme($hook, $variables = array()) {
	static $hooks = NULL;

	// If called before all modules are loaded, we do not necessarily have a full
	// theme registry to work with, and therefore cannot process the theme
	// request properly. See also _theme_load_registry().
	if (!module_load_all(NULL) && !defined('MAINTENANCE_MODE')) {
		throw new Exception(t('theme() may not be called until all modules are loaded.'));
	}

	if (!isset($hooks)) {
		drupal_theme_initialize();
		$hooks = theme_get_registry(FALSE);
	}

	// If an array of hook candidates were passed, use the first one that has an
	// implementation.
	if (is_array($hook)) {
		foreach ($hook as $candidate) {
			if (isset($hooks[$candidate])) {
				break;
			}
		}
		$hook = $candidate;
	}

	// If there's no implementation, check for more generic fallbacks. If there's
	// still no implementation, log an error and return an empty string.
	if (!isset($hooks[$hook])) {
		// Iteratively strip everything after the last '__' delimiter, until an
		// implementation is found.
		while ($pos = strrpos($hook, '__')) {
			$hook = substr($hook, 0, $pos);
			if (isset($hooks[$hook])) {
				break;
			}
		}
		if (!isset($hooks[$hook])) {
			// Only log a message when not trying theme suggestions ($hook being an
			// array).
			if (!isset($candidate)) {
				watchdog('theme', 'Theme key "@key" not found.', array('@key' => $hook), WATCHDOG_WARNING);
			}
			return '';
		}
	}

	$info = $hooks[$hook];
	global $theme_path;
	$temp = $theme_path;
	// point path_to_theme() to the currently used theme path:
	$theme_path = $info['theme path'];

	// Include a file if the theme function or variable processor is held elsewhere.
	if (!empty($info['includes'])) {
		foreach ($info['includes'] as $include_file) {
			include_once DRUPAL_ROOT . '/' . $include_file;
		}
	}

	// If a renderable array is passed as $variables, then set $variables to
	// the arguments expected by the theme function.
	if (isset($variables['#theme']) || isset($variables['#theme_wrappers'])) {
		$element = $variables;
		$variables = array();
		if (isset($info['variables'])) {
			foreach (array_keys($info['variables']) as $name) {
				if (isset($element["#$name"])) {
					$variables[$name] = $element["#$name"];
				}
			}
		}
		else {
			$variables[$info['render element']] = $element;
		}
	}

	// Merge in argument defaults.
	if (!empty($info['variables'])) {
		$variables += $info['variables'];
	}
	elseif (!empty($info['render element'])) {
		$variables += array($info['render element'] => array());
	}

	// Invoke the variable processors, if any. The processors may specify
	// alternate suggestions for which hook's template/function to use. If the
	// hook is a suggestion of a base hook, invoke the variable processors of
	// the base hook, but retain the suggestion as a high priority suggestion to
	// be used unless overridden by a variable processor function.
	if (isset($info['base hook'])) {
		$base_hook = $info['base hook'];
		$base_hook_info = $hooks[$base_hook];
		if (isset($base_hook_info['preprocess functions']) || isset($base_hook_info['process functions'])) {
			$variables['theme_hook_suggestion'] = $hook;
			$hook = $base_hook;
			$info = $base_hook_info;
		}
	}
	if (isset($info['preprocess functions']) || isset($info['process functions'])) {
		$variables['theme_hook_suggestions'] = array();
		foreach (array('preprocess functions', 'process functions') as $phase) {
			if (!empty($info[$phase])) {
				foreach ($info[$phase] as $processor_function) {
					if (function_exists($processor_function)) {
						// We don't want a poorly behaved process function changing $hook.
						$hook_clone = $hook;
						$processor_function($variables, $hook_clone);
					}
				}
			}
		}
		// If the preprocess/process functions specified hook suggestions, and the
		// suggestion exists in the theme registry, use it instead of the hook that
		// theme() was called with. This allows the preprocess/process step to
		// route to a more specific theme hook. For example, a function may call
		// theme('node', ...), but a preprocess function can add 'node__article' as
		// a suggestion, enabling a theme to have an alternate template file for
		// article nodes. Suggestions are checked in the following order:
		// - The 'theme_hook_suggestion' variable is checked first. It overrides
		//   all others.
		// - The 'theme_hook_suggestions' variable is checked in FILO order, so the
		//   last suggestion added to the array takes precedence over suggestions
		//   added earlier.
		$suggestions = array();
		if (!empty($variables['theme_hook_suggestions'])) {
			$suggestions = $variables['theme_hook_suggestions'];
		}
		if (!empty($variables['theme_hook_suggestion'])) {
			$suggestions[] = $variables['theme_hook_suggestion'];
		}
		foreach (array_reverse($suggestions) as $suggestion) {
			if (isset($hooks[$suggestion])) {
				$info = $hooks[$suggestion];
				break;
			}
		}
	}

	// Generate the output using either a function or a template.
	$output = '';
	if (isset($info['function'])) {
		if (function_exists($info['function'])) {
			$output = $info['function']($variables);
		}
	}
	else {
		// Default render function and extension.
		$render_function = 'theme_render_template';
		$extension = '.tpl.php';

		// The theme engine may use a different extension and a different renderer.
		global $theme_engine;
		if (isset($theme_engine)) {
			if ($info['type'] != 'module') {
				if (function_exists($theme_engine . '_render_template')) {
					$render_function = $theme_engine . '_render_template';
				}
				$extension_function = $theme_engine . '_extension';
				if (function_exists($extension_function)) {
					$extension = $extension_function();
				}
			}
		}

		// In some cases, a template implementation may not have had
		// template_preprocess() run (for example, if the default implementation is
		// a function, but a template overrides that default implementation). In
		// these cases, a template should still be able to expect to have access to
		// the variables provided by template_preprocess(), so we add them here if
		// they don't already exist. We don't want to run template_preprocess()
		// twice (it would be inefficient and mess up zebra striping), so we use the
		// 'directory' variable to determine if it has already run, which while not
		// completely intuitive, is reasonably safe, and allows us to save on the
		// overhead of adding some new variable to track that.
		if (!isset($variables['directory'])) {
			$default_template_variables = array();
			template_preprocess($default_template_variables, $hook);
			$variables += $default_template_variables;
		}

		// Render the output using the template file.
		$template_file = $info['template'] . $extension;
		if (isset($info['path'])) {
			$template_file = $info['path'] . '/' . $template_file;
		}
		$output = $render_function($template_file, $variables);
	}

	// restore path_to_theme()
	$theme_path = $temp;
	return $output;
}

/**
 * Return the path to the current themed element.
 *
 * It can point to the active theme or the module handling a themed implementation.
 * For example, when invoked within the scope of a theming call it will depend
 * on where the theming function is handled. If implemented from a module, it
 * will point to the module. If implemented from the active theme, it will point
 * to the active theme. When called outside the scope of a theming call, it will
 * always point to the active theme.
 */
function path_to_theme() {
	global $theme_path;

	if (!isset($theme_path)) {
		drupal_theme_initialize();
	}

	return $theme_path;
}

/**
 * Allow themes and/or theme engines to easily discover overridden theme functions.
 *
 * @param $cache
 *   The existing cache of theme hooks to test against.
 * @param $prefixes
 *   An array of prefixes to test, in reverse order of importance.
 *
 * @return $implementations
 *   The functions found, suitable for returning from hook_theme;
 */
function drupal_find_theme_functions($cache, $prefixes) {
	$implementations = array();
	$functions = get_defined_functions();

	foreach ($cache as $hook => $info) {
		foreach ($prefixes as $prefix) {
			// Find theme functions that implement possible "suggestion" variants of
			// registered theme hooks and add those as new registered theme hooks.
			// The 'pattern' key defines a common prefix that all suggestions must
			// start with. The default is the name of the hook followed by '__'. An
			// 'base hook' key is added to each entry made for a found suggestion,
			// so that common functionality can be implemented for all suggestions of
			// the same base hook. To keep things simple, deep hierarchy of
			// suggestions is not supported: each suggestion's 'base hook' key
			// refers to a base hook, not to another suggestion, and all suggestions
			// are found using the base hook's pattern, not a pattern from an
			// intermediary suggestion.
			$pattern = isset($info['pattern']) ? $info['pattern'] : ($hook . '__');
			if (!isset($info['base hook']) && !empty($pattern)) {
				$matches = preg_grep('/^' . $prefix . '_' . $pattern . '/', $functions['user']);
				if ($matches) {
					foreach ($matches as $match) {
						$new_hook = substr($match, strlen($prefix) + 1);
						$arg_name = isset($info['variables']) ? 'variables' : 'render element';
						$implementations[$new_hook] = array(
								'function' => $match,
								$arg_name => $info[$arg_name],
								'base hook' => $hook,
						);
					}
				}
			}
			// Find theme functions that implement registered theme hooks and include
			// that in what is returned so that the registry knows that the theme has
			// this implementation.
			if (function_exists($prefix . '_' . $hook)) {
				$implementations[$hook] = array(
						'function' => $prefix . '_' . $hook,
				);
			}
		}
	}

	return $implementations;
}

/**
 * Allow themes and/or theme engines to easily discover overridden templates.
 *
 * @param $cache
 *   The existing cache of theme hooks to test against.
 * @param $extension
 *   The extension that these templates will have.
 * @param $path
 *   The path to search.
 */
function drupal_find_theme_templates($cache, $extension, $path) {
	$implementations = array();

	// Collect paths to all sub-themes grouped by base themes. These will be
	// used for filtering. This allows base themes to have sub-themes in its
	// folder hierarchy without affecting the base themes template discovery.
	$theme_paths = array();
	foreach (list_themes() as $theme_info) {
		if (!empty($theme_info->base_theme)) {
			$theme_paths[$theme_info->base_theme][$theme_info->name] = dirname($theme_info->filename);
		}
	}
	foreach ($theme_paths as $basetheme => $subthemes) {
		foreach ($subthemes as $subtheme => $subtheme_path) {
			if (isset($theme_paths[$subtheme])) {
				$theme_paths[$basetheme] = array_merge($theme_paths[$basetheme], $theme_paths[$subtheme]);
			}
		}
	}
	global $theme;
	$subtheme_paths = isset($theme_paths[$theme]) ? $theme_paths[$theme] : array();

	// Escape the periods in the extension.
	$regex = '/' . str_replace('.', '\.', $extension) . '$/';
	// Get a listing of all template files in the path to search.
	$files = drupal_system_listing($regex, $path, 'name', 0);

	// Find templates that implement registered theme hooks and include that in
	// what is returned so that the registry knows that the theme has this
	// implementation.
	foreach ($files as $template => $file) {
		// Ignore sub-theme templates for the current theme.
		if (strpos($file->uri, str_replace($subtheme_paths, '', $file->uri)) !== 0) {
			continue;
		}
		// Chop off the remaining extensions if there are any. $template already
		// has the rightmost extension removed, but there might still be more,
		// such as with .tpl.php, which still has .tpl in $template at this point.
		if (($pos = strpos($template, '.')) !== FALSE) {
			$template = substr($template, 0, $pos);
		}
		// Transform - in filenames to _ to match function naming scheme
		// for the purposes of searching.
		$hook = strtr($template, '-', '_');
		if (isset($cache[$hook])) {
			$implementations[$hook] = array(
					'template' => $template,
					'path' => dirname($file->uri),
			);
		}
	}

	// Find templates that implement possible "suggestion" variants of registered
	// theme hooks and add those as new registered theme hooks. See
	// drupal_find_theme_functions() for more information about suggestions and
	// the use of 'pattern' and 'base hook'.
	$patterns = array_keys($files);
	foreach ($cache as $hook => $info) {
		$pattern = isset($info['pattern']) ? $info['pattern'] : ($hook . '__');
		if (!isset($info['base hook']) && !empty($pattern)) {
			// Transform _ in pattern to - to match file naming scheme
			// for the purposes of searching.
			$pattern = strtr($pattern, '_', '-');

			$matches = preg_grep('/^' . $pattern . '/', $patterns);
			if ($matches) {
				foreach ($matches as $match) {
					$file = substr($match, 0, strpos($match, '.'));
					// Put the underscores back in for the hook name and register this pattern.
					$arg_name = isset($info['variables']) ? 'variables' : 'render element';
					$implementations[strtr($file, '-', '_')] = array(
							'template' => $file,
							'path' => dirname($files[$match]->uri),
							$arg_name => $info[$arg_name],
							'base hook' => $hook,
					);
				}
			}
		}
	}
	return $implementations;
}

/**
 * Retrieve a setting for the current theme or for a given theme.
 *
 * The final setting is obtained from the last value found in the following
 * sources:
 * - the default global settings specified in this function
 * - the default theme-specific settings defined in any base theme's .info file
 * - the default theme-specific settings defined in the theme's .info file
 * - the saved values from the global theme settings form
 * - the saved values from the theme's settings form
 * To only retrieve the default global theme setting, an empty string should be
 * given for $theme.
 *
 * @param $setting_name
 *   The name of the setting to be retrieved.
 * @param $theme
 *   The name of a given theme; defaults to the current theme.
 *
 * @return
 *   The value of the requested setting, NULL if the setting does not exist.
 */
function theme_get_setting($setting_name, $theme = NULL) {
	$cache = &drupal_static(__FUNCTION__, array());

	// If no key is given, use the current theme if we can determine it.
	if (!isset($theme)) {
		$theme = !empty($GLOBALS['theme_key']) ? $GLOBALS['theme_key'] : '';
	}

	if (empty($cache[$theme])) {
		// Set the default values for each global setting.
		// To add new global settings, add their default values below, and then
		// add form elements to system_theme_settings() in system.admin.inc.
		$cache[$theme] = array(
				'default_logo'                     =>  1,
				'logo_path'                        =>  '',
				'default_favicon'                  =>  1,
				'favicon_path'                     =>  '',
				// Use the IANA-registered MIME type for ICO files as default.
				'favicon_mimetype'                 =>  'image/vnd.microsoft.icon',
		);
		// Turn on all default features.
		$features = _system_default_theme_features();
		foreach ($features as $feature) {
			$cache[$theme]['toggle_' . $feature] = 1;
		}

		// Get the values for the theme-specific settings from the .info files of
		// the theme and all its base themes.
		if ($theme) {
			$themes = list_themes();
			$theme_object = $themes[$theme];

			// Create a list which includes the current theme and all its base themes.
			if (isset($theme_object->base_themes)) {
				$theme_keys = array_keys($theme_object->base_themes);
				$theme_keys[] = $theme;
			}
			else {
				$theme_keys = array($theme);
			}
			foreach ($theme_keys as $theme_key) {
				if (!empty($themes[$theme_key]->info['settings'])) {
					$cache[$theme] = array_merge($cache[$theme], $themes[$theme_key]->info['settings']);
				}
			}
		}

		// Get the saved global settings from the database.
		$cache[$theme] = array_merge($cache[$theme], variable_get('theme_settings', array()));

		if ($theme) {
			// Get the saved theme-specific settings from the database.
			$cache[$theme] = array_merge($cache[$theme], variable_get('theme_' . $theme . '_settings', array()));

			// If the theme does not support a particular feature, override the global
			// setting and set the value to NULL.
			if (!empty($theme_object->info['features'])) {
				foreach ($features as $feature) {
					if (!in_array($feature, $theme_object->info['features'])) {
						$cache[$theme]['toggle_' . $feature] = NULL;
					}
				}
			}

			// Generate the path to the logo image.
			if ($cache[$theme]['toggle_logo']) {
				if ($cache[$theme]['default_logo']) {
					$cache[$theme]['logo'] = file_create_url(dirname($theme_object->filename) . '/logo.png');
				}
				elseif ($cache[$theme]['logo_path']) {
					$cache[$theme]['logo'] = file_create_url($cache[$theme]['logo_path']);
				}
			}

			// Generate the path to the favicon.
			if ($cache[$theme]['toggle_favicon']) {
				if ($cache[$theme]['default_favicon']) {
					if (file_exists($favicon = dirname($theme_object->filename) . '/favicon.ico')) {
						$cache[$theme]['favicon'] = file_create_url($favicon);
					}
					else {
						$cache[$theme]['favicon'] = file_create_url('misc/favicon.ico');
					}
				}
				elseif ($cache[$theme]['favicon_path']) {
					$cache[$theme]['favicon'] = file_create_url($cache[$theme]['favicon_path']);
				}
				else {
					$cache[$theme]['toggle_favicon'] = FALSE;
				}
			}
		}
	}

	return isset($cache[$theme][$setting_name]) ? $cache[$theme][$setting_name] : NULL;
}

/**
 * Render a system default template, which is essentially a PHP template.
 *
 * @param $template_file
 *   The filename of the template to render.
 * @param $variables
 *   A keyed array of variables that will appear in the output.
 *
 * @return
 *   The output generated by the template.
 */
function theme_render_template($template_file, $variables) {
	extract($variables, EXTR_SKIP);               // Extract the variables to a local namespace
	ob_start();                                   // Start output buffering
	include DRUPAL_ROOT . '/' . $template_file;   // Include the template file
	return ob_get_clean();                        // End buffering and return its contents
}

/**
 * Enable a given list of themes.
 *
 * @param $theme_list
 *   An array of theme names.
 */
function theme_enable($theme_list) {
	drupal_clear_css_cache();

	foreach ($theme_list as $key) {
		db_update('system')
		->fields(array('status' => 1))
		->condition('type', 'theme')
		->condition('name', $key)
		->execute();
	}

	list_themes(TRUE);
	menu_rebuild();
	drupal_theme_rebuild();

	// Invoke hook_themes_enabled() after the themes have been enabled.
	module_invoke_all('themes_enabled', $theme_list);
}

/**
 * Disable a given list of themes.
 *
 * @param $theme_list
 *   An array of theme names.
 */
function theme_disable($theme_list) {
	// Don't disable the default theme.
	if ($pos = array_search(variable_get('theme_default', 'bartik'), $theme_list) !== FALSE) {
		unset($theme_list[$pos]);
		if (empty($theme_list)) {
			return;
		}
	}

	drupal_clear_css_cache();

	foreach ($theme_list as $key) {
		db_update('system')
		->fields(array('status' => 0))
		->condition('type', 'theme')
		->condition('name', $key)
		->execute();
	}

	list_themes(TRUE);
	menu_rebuild();
	drupal_theme_rebuild();

	// Invoke hook_themes_disabled after the themes have been disabled.
	module_invoke_all('themes_disabled', $theme_list);
}

/**
 * @ingroup themeable
 * @{
 */

/**
 * Returns HTML for status and/or error messages, grouped by type.
 *
 * An invisible heading identifies the messages for assistive technology.
 * Sighted users see a colored box. See http://www.w3.org/TR/WCAG-TECHS/H69.html
 * for info.
 *
 * @param $variables
 *   An associative array containing:
 *   - display: (optional) Set to 'status' or 'error' to display only messages
 *     of that type.
 */
function theme_status_messages($variables) {
	$display = $variables['display'];
	$output = '';

	$status_heading = array(
			'status' => t('Status message'),
			'error' => t('Error message'),
			'warning' => t('Warning message'),
	);
	foreach (drupal_get_messages($display) as $type => $messages) {
		$output .= "<div class=\"messages $type\">\n";
		if (!empty($status_heading[$type])) {
			$output .= '<h2 class="element-invisible">' . $status_heading[$type] . "</h2>\n";
		}
		if (count($messages) > 1) {
			$output .= " <ul>\n";
			foreach ($messages as $message) {
				$output .= '  <li>' . $message . "</li>\n";
			}
			$output .= " </ul>\n";
		}
		else {
			$output .= $messages[0];
		}
		$output .= "</div>\n";
	}
	return $output;
}

/**
 * Returns HTML for a link.
 *
 * All Drupal code that outputs a link should call the l() function. That
 * function performs some initial preprocessing, and then, if necessary, calls
 * theme('link') for rendering the anchor tag.
 *
 * To optimize performance for sites that don't need custom theming of links,
 * the l() function includes an inline copy of this function, and uses that copy
 * if none of the enabled modules or the active theme implement any preprocess
 * or process functions or override this theme implementation.
 *
 * @param $variables
 *   An associative array containing the keys 'text', 'path', and 'options'. See
 *   the l() function for information about these variables.
 *
 * @see l()
 */
function theme_link($variables) {
	return '<a href="' . check_plain(url($variables['path'], $variables['options'])) . '"' . drupal_attributes($variables['options']['attributes']) . '>' . ($variables['options']['html'] ? $variables['text'] : check_plain($variables['text'])) . '</a>';
}

/**
 * Returns HTML for a set of links.
 *
 * @param $variables
 *   An associative array containing:
 *   - links: An associative array of links to be themed. The key for each link
 *     is used as its CSS class. Each link should be itself an array, with the
 *     following elements:
 *     - title: The link text.
 *     - href: The link URL. If omitted, the 'title' is shown as a plain text
 *       item in the links list.
 *     - html: (optional) Whether or not 'title' is HTML. If set, the title
 *       will not be passed through check_plain().
 *     - attributes: (optional) Attributes for the anchor, or for the <span> tag
 *       used in its place if no 'href' is supplied. If element 'class' is
 *       included, it must be an array of one or more class names.
 *     If the 'href' element is supplied, the entire link array is passed to l()
 *     as its $options parameter.
 *   - attributes: A keyed array of attributes for the UL containing the
 *     list of links.
 *   - heading: (optional) A heading to precede the links. May be an associative
 *     array or a string. If it's an array, it can have the following elements:
 *     - text: The heading text.
 *     - level: The heading level (e.g. 'h2', 'h3').
 *     - class: (optional) An array of the CSS classes for the heading.
 *     When using a string it will be used as the text of the heading and the
 *     level will default to 'h2'. Headings should be used on navigation menus
 *     and any list of links that consistently appears on multiple pages. To
 *     make the heading invisible use the 'element-invisible' CSS class. Do not
 *     use 'display:none', which removes it from screen-readers and assistive
 *     technology. Headings allow screen-reader and keyboard only users to
 *     navigate to or skip the links. See
 *     http://juicystudio.com/article/screen-readers-display-none.php and
 *     http://www.w3.org/TR/WCAG-TECHS/H42.html for more information.
 */
function theme_links($variables) {
	$links = $variables['links'];
	$attributes = $variables['attributes'];
	$heading = $variables['heading'];
	global $language_url;
	$output = '';

	if (count($links) > 0) {
		$output = '';

		// Treat the heading first if it is present to prepend it to the
		// list of links.
		if (!empty($heading)) {
			if (is_string($heading)) {
				// Prepare the array that will be used when the passed heading
				// is a string.
				$heading = array(
						'text' => $heading,
						// Set the default level of the heading.
						'level' => 'h2',
				);
			}
			$output .= '<' . $heading['level'];
			if (!empty($heading['class'])) {
				$output .= drupal_attributes(array('class' => $heading['class']));
			}
			$output .= '>' . check_plain($heading['text']) . '</' . $heading['level'] . '>';
		}

		$output .= '<ul' . drupal_attributes($attributes) . '>';

		$num_links = count($links);
		$i = 1;

		foreach ($links as $key => $link) {
			$class = array($key);

			// Add first, last and active classes to the list of links to help out themers.
			if ($i == 1) {
				$class[] = 'first';
			}
			if ($i == $num_links) {
				$class[] = 'last';
			}
			if (isset($link['href']) && ($link['href'] == $_GET['q'] || ($link['href'] == '<front>' && drupal_is_front_page()))
					&& (empty($link['language']) || $link['language']->language == $language_url->language)) {
				$class[] = 'active';
			}
			$output .= '<li' . drupal_attributes(array('class' => $class)) . '>';

			if (isset($link['href'])) {
				// Pass in $link as $options, they share the same keys.
				$output .= l($link['title'], $link['href'], $link);
			}
			elseif (!empty($link['title'])) {
				// Some links are actually not links, but we wrap these in <span> for adding title and class attributes.
				if (empty($link['html'])) {
					$link['title'] = check_plain($link['title']);
				}
				$span_attributes = '';
				if (isset($link['attributes'])) {
					$span_attributes = drupal_attributes($link['attributes']);
				}
				$output .= '<span' . $span_attributes . '>' . $link['title'] . '</span>';
			}

			$i++;
			$output .= "</li>\n";
		}

		$output .= '</ul>';
	}

	return $output;
}

/**
 * Returns HTML for an image.
 *
 * @param $variables
 *   An associative array containing:
 *   - path: Either the path of the image file (relative to base_path()) or a
 *     full URL.
 *   - width: The width of the image (if known).
 *   - height: The height of the image (if known).
 *   - alt: The alternative text for text-based browsers. HTML 4 and XHTML 1.0
 *     always require an alt attribute. The HTML 5 draft allows the alt
 *     attribute to be omitted in some cases. Therefore, this variable defaults
 *     to an empty string, but can be set to NULL for the attribute to be
 *     omitted. Usually, neither omission nor an empty string satisfies
 *     accessibility requirements, so it is strongly encouraged for code calling
 *     theme('image') to pass a meaningful value for this variable.
 *     - http://www.w3.org/TR/REC-html40/struct/objects.html#h-13.8
 *     - http://www.w3.org/TR/xhtml1/dtds.html
 *     - http://dev.w3.org/html5/spec/Overview.html#alt
 *   - title: The title text is displayed when the image is hovered in some
 *     popular browsers.
 *   - attributes: Associative array of attributes to be placed in the img tag.
 */
function theme_image($variables) {
	$attributes = $variables['attributes'];
	$attributes['src'] = file_create_url($variables['path']);

	foreach (array('width', 'height', 'alt', 'title') as $key) {

		if (isset($variables[$key])) {
			$attributes[$key] = $variables[$key];
		}
	}

	return '<img' . drupal_attributes($attributes) . ' />';
}

/**
 * Returns HTML for a breadcrumb trail.
 *
 * @param $variables
 *   An associative array containing:
 *   - breadcrumb: An array containing the breadcrumb links.
 */
function theme_breadcrumb($variables) {
	$breadcrumb = $variables['breadcrumb'];

	if (!empty($breadcrumb)) {
		// Provide a navigational heading to give context for breadcrumb links to
		// screen-reader users. Make the heading invisible with .element-invisible.
		$output = '<h2 class="element-invisible">' . t('You are here') . '</h2>';

		$output .= '<div class="breadcrumb">' . implode(' » ', $breadcrumb) . '</div>';
		return $output;
	}
}

/**
 * Returns HTML for a table.
 *
 * @param $variables
 *   An associative array containing:
 *   - header: An array containing the table headers. Each element of the array
 *     can be either a localized string or an associative array with the
 *     following keys:
 *     - "data": The localized title of the table column.
 *     - "field": The database field represented in the table column (required
 *       if user is to be able to sort on this column).
 *     - "sort": A default sort order for this column ("asc" or "desc").
 *     - Any HTML attributes, such as "colspan", to apply to the column header
 *       cell.
 *   - rows: An array of table rows. Every row is an array of cells, or an
 *     associative array with the following keys:
 *     - "data": an array of cells
 *     - Any HTML attributes, such as "class", to apply to the table row.
 *     - "no_striping": a boolean indicating that the row should receive no
 *       'even / odd' styling. Defaults to FALSE.
 *     Each cell can be either a string or an associative array with the
 *     following keys:
 *     - "data": The string to display in the table cell.
 *     - "header": Indicates this cell is a header.
 *     - Any HTML attributes, such as "colspan", to apply to the table cell.
 *     Here's an example for $rows:
 *     @code
 *     $rows = array(
 *       // Simple row
 *       array(
 *         'Cell 1', 'Cell 2', 'Cell 3'
 *       ),
 *       // Row with attributes on the row and some of its cells.
 *       array(
 *         'data' => array('Cell 1', array('data' => 'Cell 2', 'colspan' => 2)), 'class' => array('funky')
 *       )
 *     );
 *     @endcode
 *   - attributes: An array of HTML attributes to apply to the table tag.
 *   - caption: A localized string to use for the <caption> tag.
 *   - colgroups: An array of column groups. Each element of the array can be
 *     either:
 *     - An array of columns, each of which is an associative array of HTML
 *       attributes applied to the COL element.
 *     - An array of attributes applied to the COLGROUP element, which must
 *       include a "data" attribute. To add attributes to COL elements, set the
 *       "data" attribute with an array of columns, each of which is an
 *       associative array of HTML attributes.
 *     Here's an example for $colgroup:
 *     @code
 *     $colgroup = array(
 *       // COLGROUP with one COL element.
 *       array(
 *         array(
 *           'class' => array('funky'), // Attribute for the COL element.
 *         ),
 *       ),
 *       // Colgroup with attributes and inner COL elements.
 *       array(
 *         'data' => array(
 *           array(
 *             'class' => array('funky'), // Attribute for the COL element.
 *           ),
 *         ),
 *         'class' => array('jazzy'), // Attribute for the COLGROUP element.
 *       ),
 *     );
 *     @endcode
 *     These optional tags are used to group and set properties on columns
 *     within a table. For example, one may easily group three columns and
 *     apply same background style to all.
 *   - sticky: Use a "sticky" table header.
 *   - empty: The message to display in an extra row if table does not have any
 *     rows.
 */
function theme_table($variables) {
	$header = $variables['header'];
	$rows = $variables['rows'];
	$attributes = $variables['attributes'];
	$caption = $variables['caption'];
	$colgroups = $variables['colgroups'];
	$sticky = $variables['sticky'];
	$empty = $variables['empty'];

	// Add sticky headers, if applicable.
	if (count($header) && $sticky) {
		drupal_add_js('misc/tableheader.js');
		// Add 'sticky-enabled' class to the table to identify it for JS.
		// This is needed to target tables constructed by this function.
		$attributes['class'][] = 'sticky-enabled';
	}

	$output = '<table' . drupal_attributes($attributes) . ">\n";

	if (isset($caption)) {
		$output .= '<caption>' . $caption . "</caption>\n";
	}

	// Format the table columns:
	if (count($colgroups)) {
		foreach ($colgroups as $number => $colgroup) {
			$attributes = array();

			// Check if we're dealing with a simple or complex column
			if (isset($colgroup['data'])) {
				foreach ($colgroup as $key => $value) {
					if ($key == 'data') {
						$cols = $value;
					}
					else {
						$attributes[$key] = $value;
					}
				}
			}
			else {
				$cols = $colgroup;
			}

			// Build colgroup
			if (is_array($cols) && count($cols)) {
				$output .= ' <colgroup' . drupal_attributes($attributes) . '>';
				$i = 0;
				foreach ($cols as $col) {
					$output .= ' <col' . drupal_attributes($col) . ' />';
				}
				$output .= " </colgroup>\n";
			}
			else {
				$output .= ' <colgroup' . drupal_attributes($attributes) . " />\n";
			}
		}
	}

	// Add the 'empty' row message if available.
	if (!count($rows) && $empty) {
		$header_count = 0;
		foreach ($header as $header_cell) {
			if (is_array($header_cell)) {
				$header_count += isset($header_cell['colspan']) ? $header_cell['colspan'] : 1;
			}
			else {
				$header_count++;
			}
		}
		$rows[] = array(array('data' => $empty, 'colspan' => $header_count, 'class' => array('empty', 'message')));
	}

	// Format the table header:
	if (count($header)) {
		$ts = tablesort_init($header);
		// HTML requires that the thead tag has tr tags in it followed by tbody
		// tags. Using ternary operator to check and see if we have any rows.
		$output .= (count($rows) ? ' <thead><tr>' : ' <tr>');
		foreach ($header as $cell) {
			$cell = tablesort_header($cell, $header, $ts);
			$output .= _theme_table_cell($cell, TRUE);
		}
		// Using ternary operator to close the tags based on whether or not there are rows
		$output .= (count($rows) ? " </tr></thead>\n" : "</tr>\n");
	}
	else {
		$ts = array();
	}

	// Format the table rows:
	if (count($rows)) {
		$output .= "<tbody>\n";
		$flip = array('even' => 'odd', 'odd' => 'even');
		$class = 'even';
		foreach ($rows as $number => $row) {
			$attributes = array();

			// Check if we're dealing with a simple or complex row
			if (isset($row['data'])) {
				foreach ($row as $key => $value) {
					if ($key == 'data') {
						$cells = $value;
					}
					else {
						$attributes[$key] = $value;
					}
				}
			}
			else {
				$cells = $row;
			}
			if (count($cells)) {
				// Add odd/even class
				if (empty($row['no_striping'])) {
					$class = $flip[$class];
					$attributes['class'][] = $class;
				}

				// Build row
				$output .= ' <tr' . drupal_attributes($attributes) . '>';
				$i = 0;
				foreach ($cells as $cell) {
					$cell = tablesort_cell($cell, $header, $ts, $i++);
					$output .= _theme_table_cell($cell);
				}
				$output .= " </tr>\n";
			}
		}
		$output .= "</tbody>\n";
	}

	$output .= "</table>\n";
	return $output;
}

/**
 * Returns HTML for a sort icon.
 *
 * @param $variables
 *   An associative array containing:
 *   - style: Set to either 'asc' or 'desc', this determines which icon to show.
 */
function theme_tablesort_indicator($variables) {
	if ($variables['style'] == "asc") {
		return theme('image', array('path' => 'misc/arrow-asc.png', 'width' => 13, 'height' => 13, 'alt' => t('sort ascending'), 'title' => t('sort ascending')));
	}
	else {
		return theme('image', array('path' => 'misc/arrow-desc.png', 'width' => 13, 'height' => 13, 'alt' => t('sort descending'), 'title' => t('sort descending')));
	}
}

/**
 * Returns HTML for a marker for new or updated content.
 *
 * @param $variables
 *   An associative array containing:
 *   - type: Number representing the marker type to display. See MARK_NEW,
 *     MARK_UPDATED, MARK_READ.
 */
function theme_mark($variables) {
	$type = $variables['type'];
	global $user;
	if ($user->uid) {
		if ($type == MARK_NEW) {
			return ' <span class="marker">' . t('new') . '</span>';
		}
		elseif ($type == MARK_UPDATED) {
			return ' <span class="marker">' . t('updated') . '</span>';
		}
	}
}

/**
 * Returns HTML for a list or nested list of items.
 *
 * @param $variables
 *   An associative array containing:
 *   - items: An array of items to be displayed in the list. If an item is a
 *     string, then it is used as is. If an item is an array, then the "data"
 *     element of the array is used as the contents of the list item. If an item
 *     is an array with a "children" element, those children are displayed in a
 *     nested list. All other elements are treated as attributes of the list
 *     item element.
 *   - title: The title of the list.
 *   - type: The type of list to return (e.g. "ul", "ol").
 *   - attributes: The attributes applied to the list element.
 */
function theme_item_list($variables) {
	$items = $variables['items'];
	$title = $variables['title'];
	$type = $variables['type'];
	$attributes = $variables['attributes'];

	$output = '<div class="item-list">';
	if (isset($title)) {
		$output .= '<h3>' . $title . '</h3>';
	}

	if (!empty($items)) {
		$output .= "<$type" . drupal_attributes($attributes) . '>';
		$num_items = count($items);
		foreach ($items as $i => $item) {
			$attributes = array();
			$children = array();
			$data = '';
			if (is_array($item)) {
				foreach ($item as $key => $value) {
					if ($key == 'data') {
						$data = $value;
					}
					elseif ($key == 'children') {
						$children = $value;
					}
					else {
						$attributes[$key] = $value;
					}
				}
			}
			else {
				$data = $item;
			}
			if (count($children) > 0) {
				// Render nested list.
				$data .= theme_item_list(array('items' => $children, 'title' => NULL, 'type' => $type, 'attributes' => $attributes));
			}
			if ($i == 0) {
				$attributes['class'][] = 'first';
			}
			if ($i == $num_items - 1) {
				$attributes['class'][] = 'last';
			}
			$output .= '<li' . drupal_attributes($attributes) . '>' . $data . "</li>\n";
		}
		$output .= "</$type>";
	}
	$output .= '</div>';
	return $output;
}

/**
 * Returns HTML for a "more help" link.
 *
 * @param $variables
 *   An associative array containing:
 *   - url: The url for the link.
 */
function theme_more_help_link($variables) {
	return '<div class="more-help-link">' . l(t('More help'), $variables['url']) . '</div>';
}

/**
 * Returns HTML for a feed icon.
 *
 * @param $variables
 *   An associative array containing:
 *   - url: An internal system path or a fully qualified external URL of the
 *     feed.
 *   - title: A descriptive title of the feed.
 */
function theme_feed_icon($variables) {
	$text = t('Subscribe to @feed-title', array('@feed-title' => $variables['title']));
	if ($image = theme('image', array('path' => 'misc/feed.png', 'width' => 16, 'height' => 16, 'alt' => $text))) {
		return l($image, $variables['url'], array('html' => TRUE, 'attributes' => array('class' => array('feed-icon'), 'title' => $text)));
	}
}

/**
 * Returns HTML for a generic HTML tag with attributes.
 *
 * @param $variables
 *   An associative array containing:
 *   - element: An associative array describing the tag:
 *     - #tag: The tag name to output. Typical tags added to the HTML HEAD:
 *       - meta: To provide meta information, such as a page refresh.
 *       - link: To refer to stylesheets and other contextual information.
 *       - script: To load JavaScript.
 *     - #attributes: (optional) An array of HTML attributes to apply to the
 *       tag.
 *     - #value: (optional) A string containing tag content, such as inline CSS.
 *     - #value_prefix: (optional) A string to prepend to #value, e.g. a CDATA
 *       wrapper prefix.
 *     - #value_suffix: (optional) A string to append to #value, e.g. a CDATA
 *       wrapper suffix.
 */
function theme_html_tag($variables) {
	$element = $variables['element'];
	$attributes = isset($element['#attributes']) ? drupal_attributes($element['#attributes']) : '';
	if (!isset($element['#value'])) {
		return '<' . $element['#tag'] . $attributes . " />\n";
	}
	else {
		$output = '<' . $element['#tag'] . $attributes . '>';
		if (isset($element['#value_prefix'])) {
			$output .= $element['#value_prefix'];
		}
		$output .= $element['#value'];
		if (isset($element['#value_suffix'])) {
			$output .= $element['#value_suffix'];
		}
		$output .= '</' . $element['#tag'] . ">\n";
		return $output;
	}
}

/**
 * Returns HTML for a "more" link, like those used in blocks.
 *
 * @param $variables
 *   An associative array containing:
 *   - url: The url of the main page.
 *   - title: A descriptive verb for the link, like 'Read more'.
 */
function theme_more_link($variables) {
	return '<div class="more-link">' . l(t('More'), $variables['url'], array('attributes' => array('title' => $variables['title']))) . '</div>';
}

/**
 * Returns HTML for a username, potentially linked to the user's page.
 *
 * @param $variables
 *   An associative array containing:
 *   - account: The user object to format.
 *   - name: The user's name, sanitized.
 *   - extra: Additional text to append to the user's name, sanitized.
 *   - link_path: The path or URL of the user's profile page, home page, or
 *     other desired page to link to for more information about the user.
 *   - link_options: An array of options to pass to the l() function's $options
 *     parameter if linking the user's name to the user's page.
 *   - attributes_array: An array of attributes to pass to the
 *     drupal_attributes() function if not linking to the user's page.
 *
 * @see template_preprocess_username()
 * @see template_process_username()
 */
function theme_username($variables) {
	if (isset($variables['link_path'])) {
		// We have a link path, so we should generate a link using l().
		// Additional classes may be added as array elements like
		// $variables['link_options']['attributes']['class'][] = 'myclass';
		$output = l($variables['name'] . $variables['extra'], $variables['link_path'], $variables['link_options']);
	}
	else {
		// Modules may have added important attributes so they must be included
		// in the output. Additional classes may be added as array elements like
		// $variables['attributes_array']['class'][] = 'myclass';
		$output = '<span' . drupal_attributes($variables['attributes_array']) . '>' . $variables['name'] . $variables['extra'] . '</span>';
	}
	return $output;
}

/**
 * Returns HTML for a progress bar.
 *
 * Note that the core Batch API uses this only for non-JavaScript batch jobs.
 *
 * @param $variables
 *   An associative array containing:
 *   - percent: The percentage of the progress.
 *   - message: A string containing information to be displayed.
 */
function theme_progress_bar($variables) {
	$output = '<div id="progress" class="progress">';
	$output .= '<div class="bar"><div class="filled" style="width: ' . $variables['percent'] . '%"></div></div>';
	$output .= '<div class="percentage">' . $variables['percent'] . '%</div>';
	$output .= '<div class="message">' . $variables['message'] . '</div>';
	$output .= '</div>';

	return $output;
}

/**
 * Returns HTML for an indentation div; used for drag and drop tables.
 *
 * @param $variables
 *   An associative array containing:
 *   - size: Optional. The number of indentations to create.
 */
function theme_indentation($variables) {
	$output = '';
	for ($n = 0; $n < $variables['size']; $n++) {
		$output .= '<div class="indentation">&nbsp;</div>';
	}
	return $output;
}

/**
 * @} End of "ingroup themeable".
 */

/**
 * Returns HTML output for a single table cell for theme_table().
 *
 * @param $cell
 *   Array of cell information, or string to display in cell.
 * @param bool $header
 *   TRUE if this cell is a table header cell, FALSE if it is an ordinary
 *   table cell. If $cell is an array with element 'header' set to TRUE, that
 *   will override the $header parameter.
 *
 * @return
 *   HTML for the cell.
 */
function _theme_table_cell($cell, $header = FALSE) {
	$attributes = '';

	if (is_array($cell)) {
		$data = isset($cell['data']) ? $cell['data'] : '';
		// Cell's data property can be a string or a renderable array.
		if (is_array($data)) {
			$data = drupal_render($data);
		}
		$header |= isset($cell['header']);
		unset($cell['data']);
		unset($cell['header']);
		$attributes = drupal_attributes($cell);
	}
	else {
		$data = $cell;
	}

	if ($header) {
		$output = "<th$attributes>$data</th>";
	}
	else {
		$output = "<td$attributes>$data</td>";
	}

	return $output;
}

/**
 * Adds a default set of helper variables for variable processors and templates.
 * This comes in before any other preprocess function which makes it possible to
 * be used in default theme implementations (non-overridden theme functions).
 *
 * For more detailed information, see theme().
 *
 */
function template_preprocess(&$variables, $hook) {
	global $user;
	static $count = array();

	// Track run count for each hook to provide zebra striping.
	// See "template_preprocess_block()" which provides the same feature specific to blocks.
	$count[$hook] = isset($count[$hook]) && is_int($count[$hook]) ? $count[$hook] : 1;
	$variables['zebra'] = ($count[$hook] % 2) ? 'odd' : 'even';
	$variables['id'] = $count[$hook]++;

	// Tell all templates where they are located.
	$variables['directory'] = path_to_theme();

	// Initialize html class attribute for the current hook.
	$variables['classes_array'] = array(drupal_html_class($hook));

	// Merge in variables that don't depend on hook and don't change during a
	// single page request.
	// Use the advanced drupal_static() pattern, since this is called very often.
	static $drupal_static_fast;
	if (!isset($drupal_static_fast)) {
		$drupal_static_fast['default_variables'] = &drupal_static(__FUNCTION__);
	}
	$default_variables = &$drupal_static_fast['default_variables'];
	// Global $user object shouldn't change during a page request once rendering
	// has started, but if there's an edge case where it does, re-fetch the
	// variables appropriate for the new user.
	if (!isset($default_variables) || ($user !== $default_variables['user'])) {
		$default_variables = _template_preprocess_default_variables();
	}
	$variables += $default_variables;
}

/**
 * Returns hook-independent variables to template_preprocess().
 */
function _template_preprocess_default_variables() {
	global $user;

	// Variables that don't depend on a database connection.
	$variables = array(
			'attributes_array' => array(),
			'title_attributes_array' => array(),
			'content_attributes_array' => array(),
			'title_prefix' => array(),
			'title_suffix' => array(),
			'user' => $user,
			'db_is_active' => !defined('MAINTENANCE_MODE'),
			'is_admin' => FALSE,
			'logged_in' => FALSE,
	);

	// The user object has no uid property when the database does not exist during
	// install. The user_access() check deals with issues when in maintenance mode
	// as uid is set but the user.module has not been included.
	if (isset($user->uid) && function_exists('user_access')) {
		$variables['is_admin'] = user_access('access administration pages');
		$variables['logged_in'] = ($user->uid > 0);
	}

	// drupal_is_front_page() might throw an exception.
	try {
		$variables['is_front'] = drupal_is_front_page();
	}
	catch (Exception $e) {
		// If the database is not yet available, set default values for these
		// variables.
		$variables['is_front'] = FALSE;
		$variables['db_is_active'] = FALSE;
	}

	return $variables;
}

/**
 * A default process function used to alter variables as late as possible.
 *
 * For more detailed information, see theme().
 *
 */
function template_process(&$variables, $hook) {
	// Flatten out classes.
	$variables['classes'] = implode(' ', $variables['classes_array']);

	// Flatten out attributes, title_attributes, and content_attributes.
	// Because this function can be called very often, and often with empty
	// attributes, optimize performance by only calling drupal_attributes() if
	// necessary.
	$variables['attributes'] = $variables['attributes_array'] ? drupal_attributes($variables['attributes_array']) : '';
	$variables['title_attributes'] = $variables['title_attributes_array'] ? drupal_attributes($variables['title_attributes_array']) : '';
	$variables['content_attributes'] = $variables['content_attributes_array'] ? drupal_attributes($variables['content_attributes_array']) : '';
}

/**
 * Preprocess variables for html.tpl.php
 *
 * @see system_elements()
 * @see html.tpl.php
 */
function template_preprocess_html(&$variables) {
	// Compile a list of classes that are going to be applied to the body element.
	// This allows advanced theming based on context (home page, node of certain type, etc.).
	// Add a class that tells us whether we're on the front page or not.
	$variables['classes_array'][] = $variables['is_front'] ? 'front' : 'not-front';
	// Add a class that tells us whether the page is viewed by an authenticated user or not.
	$variables['classes_array'][] = $variables['logged_in'] ? 'logged-in' : 'not-logged-in';

	// Add information about the number of sidebars.
	if (!empty($variables['page']['sidebar_first']) && !empty($variables['page']['sidebar_second'])) {
		$variables['classes_array'][] = 'two-sidebars';
	}
	elseif (!empty($variables['page']['sidebar_first'])) {
		$variables['classes_array'][] = 'one-sidebar sidebar-first';
	}
	elseif (!empty($variables['page']['sidebar_second'])) {
		$variables['classes_array'][] = 'one-sidebar sidebar-second';
	}
	else {
		$variables['classes_array'][] = 'no-sidebars';
	}

	// Populate the body classes.
	if ($suggestions = theme_get_suggestions(arg(), 'page', '-')) {
		foreach ($suggestions as $suggestion) {
			if ($suggestion != 'page-front') {
				// Add current suggestion to page classes to make it possible to theme
				// the page depending on the current page type (e.g. node, admin, user,
				// etc.) as well as more specific data like node-12 or node-edit.
				$variables['classes_array'][] = drupal_html_class($suggestion);
			}
		}
	}

	// If on an individual node page, add the node type to body classes.
	if ($node = menu_get_object()) {
		$variables['classes_array'][] = drupal_html_class('node-type-' . $node->type);
	}

	// RDFa allows annotation of XHTML pages with RDF data, while GRDDL provides
	// mechanisms for extraction of this RDF content via XSLT transformation
	// using an associated GRDDL profile.
	$variables['rdf_namespaces']    = drupal_get_rdf_namespaces();
	$variables['grddl_profile']     = 'http://www.w3.org/1999/xhtml/vocab';
	$variables['language']          = $GLOBALS['language'];
	$variables['language']->dir     = $GLOBALS['language']->direction ? 'rtl' : 'ltr';

	// Add favicon.
	if (theme_get_setting('toggle_favicon')) {
		$favicon = theme_get_setting('favicon');
		$type = theme_get_setting('favicon_mimetype');
		drupal_add_html_head_link(array('rel' => 'shortcut icon', 'href' => drupal_strip_dangerous_protocols($favicon), 'type' => $type));
	}

	// Construct page title.
	if (drupal_get_title()) {
		$head_title = array(
				'title' => strip_tags(drupal_get_title()),
				'name' => check_plain(variable_get('site_name', 'Drupal')),
		);
	}
	else {
		$head_title = array('name' => check_plain(variable_get('site_name', 'Drupal')));
		if (variable_get('site_slogan', '')) {
			$head_title['slogan'] = filter_xss_admin(variable_get('site_slogan', ''));
		}
	}
	$variables['head_title_array'] = $head_title;
	$variables['head_title'] = implode(' | ', $head_title);

	// Populate the page template suggestions.
	if ($suggestions = theme_get_suggestions(arg(), 'html')) {
		$variables['theme_hook_suggestions'] = $suggestions;
	}
}

/**
 * Preprocess variables for page.tpl.php
 *
 * Most themes utilize their own copy of page.tpl.php. The default is located
 * inside "modules/system/page.tpl.php". Look in there for the full list of
 * variables.
 *
 * Uses the arg() function to generate a series of page template suggestions
 * based on the current path.
 *
 * Any changes to variables in this preprocessor should also be changed inside
 * template_preprocess_maintenance_page() to keep all of them consistent.
 *
 * @see drupal_render_page()
 * @see template_process_page()
 * @see page.tpl.php
 */
function template_preprocess_page(&$variables) {
	// Move some variables to the top level for themer convenience and template cleanliness.
	$variables['show_messages'] = $variables['page']['#show_messages'];

	foreach (system_region_list($GLOBALS['theme']) as $region_key => $region_name) {
		if (!isset($variables['page'][$region_key])) {
			$variables['page'][$region_key] = array();
		}
	}

	// Set up layout variable.
	$variables['layout'] = 'none';
	if (!empty($variables['page']['sidebar_first'])) {
		$variables['layout'] = 'first';
	}
	if (!empty($variables['page']['sidebar_second'])) {
		$variables['layout'] = ($variables['layout'] == 'first') ? 'both' : 'second';
	}

	$variables['base_path']         = base_path();
	$variables['front_page']        = url();
	$variables['feed_icons']        = drupal_get_feeds();
	$variables['language']          = $GLOBALS['language'];
	$variables['language']->dir     = $GLOBALS['language']->direction ? 'rtl' : 'ltr';
	$variables['logo']              = theme_get_setting('logo');
	$variables['main_menu']         = theme_get_setting('toggle_main_menu') ? menu_main_menu() : array();
	$variables['secondary_menu']    = theme_get_setting('toggle_secondary_menu') ? menu_secondary_menu() : array();
	$variables['action_links']      = menu_local_actions();
	$variables['site_name']         = (theme_get_setting('toggle_name') ? filter_xss_admin(variable_get('site_name', 'Drupal')) : '');
	$variables['site_slogan']       = (theme_get_setting('toggle_slogan') ? filter_xss_admin(variable_get('site_slogan', '')) : '');
	$variables['tabs']              = menu_local_tabs();

	if ($node = menu_get_object()) {
		$variables['node'] = $node;
	}

	// Populate the page template suggestions.
	if ($suggestions = theme_get_suggestions(arg(), 'page')) {
		$variables['theme_hook_suggestions'] = $suggestions;
	}
}

/**
 * Process variables for page.tpl.php
 *
 * Perform final addition of variables before passing them into the template.
 * To customize these variables, simply set them in an earlier step.
 *
 * @see template_preprocess_page()
 * @see page.tpl.php
 */
function template_process_page(&$variables) {
	if (!isset($variables['breadcrumb'])) {
		// Build the breadcrumb last, so as to increase the chance of being able to
		// re-use the cache of an already rendered menu containing the active link
		// for the current page.
		// @see menu_tree_page_data()
		$variables['breadcrumb'] = theme('breadcrumb', array('breadcrumb' => drupal_get_breadcrumb()));
	}
	if (!isset($variables['title'])) {
		$variables['title'] = drupal_get_title();
	}

	// Generate messages last in order to capture as many as possible for the
	// current page.
	if (!isset($variables['messages'])) {
		$variables['messages'] = $variables['show_messages'] ? theme('status_messages') : '';
	}
}

/**
 * Process variables for html.tpl.php
 *
 * Perform final addition and modification of variables before passing into
 * the template. To customize these variables, call drupal_render() on elements
 * in $variables['page'] during THEME_preprocess_page().
 *
 * @see template_preprocess_html()
 * @see html.tpl.php
 */
function template_process_html(&$variables) {
	// Render page_top and page_bottom into top level variables.
	$variables['page_top'] = drupal_render($variables['page']['page_top']);
	$variables['page_bottom'] = drupal_render($variables['page']['page_bottom']);
	// Place the rendered HTML for the page body into a top level variable.
	$variables['page']              = $variables['page']['#children'];
	$variables['page_bottom'] .= drupal_get_js('footer');

	$variables['head']    = drupal_get_html_head();
	$variables['css']     = drupal_add_css();
	$variables['styles']  = drupal_get_css();
	$variables['scripts'] = drupal_get_js();
}

/**
 * Generate an array of suggestions from path arguments.
 *
 * This is typically called for adding to the 'theme_hook_suggestions' or
 * 'classes_array' variables from within preprocess functions, when wanting to
 * base the additional suggestions on the path of the current page.
 *
 * @param $args
 *   An array of path arguments, such as from function arg().
 * @param $base
 *   A string identifying the base 'thing' from which more specific suggestions
 *   are derived. For example, 'page' or 'html'.
 * @param $delimiter
 *   The string used to delimit increasingly specific information. The default
 *   of '__' is appropriate for theme hook suggestions. '-' is appropriate for
 *   extra classes.
 *
 * @return
 *   An array of suggestions, suitable for adding to
 *   $variables['theme_hook_suggestions'] within a preprocess function or to
 *   $variables['classes_array'] if the suggestions represent extra CSS classes.
 */
function theme_get_suggestions($args, $base, $delimiter = '__') {

	// Build a list of suggested theme hooks or body classes in order of
	// specificity. One suggestion is made for every element of the current path,
	// though numeric elements are not carried to subsequent suggestions. For
	// example, for $base='page', http://www.example.com/node/1/edit would result
	// in the following suggestions and body classes:
	//
	// page__node              page-node
	// page__node__%           page-node-%
	// page__node__1           page-node-1
	// page__node__edit        page-node-edit

	$suggestions = array();
	$prefix = $base;
	foreach ($args as $arg) {
		// Remove slashes or null per SA-CORE-2009-003 and change - (hyphen) to _
		// (underscore).
		//
		// When we discover templates in @see drupal_find_theme_templates,
		// hyphens (-) are converted to underscores (_) before the theme hook
		// is registered. We do this because the hyphens used for delimiters
		// in hook suggestions cannot be used in the function names of the
		// associated preprocess functions. Any page templates designed to be used
		// on paths that contain a hyphen are also registered with these hyphens
		// converted to underscores so here we must convert any hyphens in path
		// arguments to underscores here before fetching theme hook suggestions
		// to ensure the templates are appropriately recognized.
		$arg = str_replace(array("/", "\\", "\0", '-'), array('', '', '', '_'), $arg);
		// The percent acts as a wildcard for numeric arguments since
		// asterisks are not valid filename characters on many filesystems.
		if (is_numeric($arg)) {
			$suggestions[] = $prefix . $delimiter . '%';
		}
		$suggestions[] = $prefix . $delimiter . $arg;
		if (!is_numeric($arg)) {
			$prefix .= $delimiter . $arg;
		}
	}
	if (drupal_is_front_page()) {
		// Front templates should be based on root only, not prefixed arguments.
		$suggestions[] = $base . $delimiter . 'front';
	}

	return $suggestions;
}

/**
 * The variables array generated here is a mirror of template_preprocess_page().
 * This preprocessor will run its course when theme_maintenance_page() is
 * invoked.
 *
 * An alternate template file of "maintenance-page--offline.tpl.php" can be
 * used when the database is offline to hide errors and completely replace the
 * content.
 *
 * The $variables array contains the following arguments:
 * - $content
 *
 * @see maintenance-page.tpl.php
 */
function template_preprocess_maintenance_page(&$variables) {
	// Add favicon
	if (theme_get_setting('toggle_favicon')) {
		$favicon = theme_get_setting('favicon');
		$type = theme_get_setting('favicon_mimetype');
		drupal_add_html_head_link(array('rel' => 'shortcut icon', 'href' => drupal_strip_dangerous_protocols($favicon), 'type' => $type));
	}

	global $theme;
	// Retrieve the theme data to list all available regions.
	$theme_data = list_themes();
	$regions = $theme_data[$theme]->info['regions'];

	// Get all region content set with drupal_add_region_content().
	foreach (array_keys($regions) as $region) {
		// Assign region to a region variable.
		$region_content = drupal_get_region_content($region);
		isset($variables[$region]) ? $variables[$region] .= $region_content : $variables[$region] = $region_content;
	}

	// Setup layout variable.
	$variables['layout'] = 'none';
	if (!empty($variables['sidebar_first'])) {
		$variables['layout'] = 'first';
	}
	if (!empty($variables['sidebar_second'])) {
		$variables['layout'] = ($variables['layout'] == 'first') ? 'both' : 'second';
	}

	// Construct page title
	if (drupal_get_title()) {
		$head_title = array(
				'title' => strip_tags(drupal_get_title()),
				'name' => variable_get('site_name', 'Drupal'),
		);
	}
	else {
		$head_title = array('name' => variable_get('site_name', 'Drupal'));
		if (variable_get('site_slogan', '')) {
			$head_title['slogan'] = variable_get('site_slogan', '');
		}
	}

	// set the default language if necessary
	$language = isset($GLOBALS['language']) ? $GLOBALS['language'] : language_default();

	$variables['head_title_array']  = $head_title;
	$variables['head_title']        = implode(' | ', $head_title);
	$variables['base_path']         = base_path();
	$variables['front_page']        = url();
	$variables['breadcrumb']        = '';
	$variables['feed_icons']        = '';
	$variables['help']              = '';
	$variables['language']          = $language;
	$variables['language']->dir     = $language->direction ? 'rtl' : 'ltr';
	$variables['logo']              = theme_get_setting('logo');
	$variables['messages']          = $variables['show_messages'] ? theme('status_messages') : '';
	$variables['main_menu']         = array();
	$variables['secondary_menu']    = array();
	$variables['site_name']         = (theme_get_setting('toggle_name') ? variable_get('site_name', 'Drupal') : '');
	$variables['site_slogan']       = (theme_get_setting('toggle_slogan') ? variable_get('site_slogan', '') : '');
	$variables['tabs']              = '';
	$variables['title']             = drupal_get_title();

	// Compile a list of classes that are going to be applied to the body element.
	$variables['classes_array'][] = 'in-maintenance';
	if (isset($variables['db_is_active']) && !$variables['db_is_active']) {
		$variables['classes_array'][] = 'db-offline';
	}
	if ($variables['layout'] == 'both') {
		$variables['classes_array'][] = 'two-sidebars';
	}
	elseif ($variables['layout'] == 'none') {
		$variables['classes_array'][] = 'no-sidebars';
	}
	else {
		$variables['classes_array'][] = 'one-sidebar sidebar-' . $variables['layout'];
	}

	// Dead databases will show error messages so supplying this template will
	// allow themers to override the page and the content completely.
	if (isset($variables['db_is_active']) && !$variables['db_is_active']) {
		$variables['theme_hook_suggestion'] = 'maintenance_page__offline';
	}
}

/**
 * The variables array generated here is a mirror of template_process_html().
 * This processor will run its course when theme_maintenance_page() is invoked.
 *
 * @see maintenance-page.tpl.php
 */
function template_process_maintenance_page(&$variables) {
	$variables['head']    = drupal_get_html_head();
	$variables['css']     = drupal_add_css();
	$variables['styles']  = drupal_get_css();
	$variables['scripts'] = drupal_get_js();
}

/**
 * Preprocess variables for region.tpl.php
 *
 * Prepare the values passed to the theme_region function to be passed into a
 * pluggable template engine. Uses the region name to generate a template file
 * suggestions. If none are found, the default region.tpl.php is used.
 *
 * @see drupal_region_class()
 * @see region.tpl.php
 */
function template_preprocess_region(&$variables) {
	// Create the $content variable that templates expect.
	$variables['content'] = $variables['elements']['#children'];
	$variables['region'] = $variables['elements']['#region'];

	$variables['classes_array'][] = drupal_region_class($variables['region']);
	$variables['theme_hook_suggestions'][] = 'region__' . $variables['region'];
}

/**
 * Preprocesses variables for theme_username().
 *
 * Modules that make any changes to variables like 'name' or 'extra' must insure
 * that the final string is safe to include directly in the output by using
 * check_plain() or filter_xss().
 *
 * @see template_process_username()
 */
function template_preprocess_username(&$variables) {
	$account = $variables['account'];

	$variables['extra'] = '';
	if (empty($account->uid)) {
		$variables['uid'] = 0;
		if (theme_get_setting('toggle_comment_user_verification')) {
			$variables['extra'] = ' (' . t('not verified') . ')';
		}
	}
	else {
		$variables['uid'] = (int) $account->uid;
	}

	// Set the name to a formatted name that is safe for printing and
	// that won't break tables by being too long. Keep an unshortened,
	// unsanitized version, in case other preprocess functions want to implement
	// their own shortening logic or add markup. If they do so, they must ensure
	// that $variables['name'] is safe for printing.
	$name = $variables['name_raw'] = format_username($account);
	if (drupal_strlen($name) > 20) {
		$name = drupal_substr($name, 0, 15) . '...';
	}
	$variables['name'] = check_plain($name);

	$variables['profile_access'] = user_access('access user profiles');
	$variables['link_attributes'] = array();
	// Populate link path and attributes if appropriate.
	if ($variables['uid'] && $variables['profile_access']) {
		// We are linking to a local user.
		$variables['link_attributes'] = array('title' => t('View user profile.'));
		$variables['link_path'] = 'user/' . $variables['uid'];
	}
	elseif (!empty($account->homepage)) {
		// Like the 'class' attribute, the 'rel' attribute can hold a
		// space-separated set of values, so initialize it as an array to make it
		// easier for other preprocess functions to append to it.
		$variables['link_attributes'] = array('rel' => array('nofollow'));
		$variables['link_path'] = $account->homepage;
		$variables['homepage'] = $account->homepage;
	}
	// We do not want the l() function to check_plain() a second time.
	$variables['link_options']['html'] = TRUE;
	// Set a default class.
	$variables['attributes_array'] = array('class' => array('username'));
}

/**
 * Processes variables for theme_username().
 *
 * @see template_preprocess_username()
 */
function template_process_username(&$variables) {
	// Finalize the link_options array for passing to the l() function.
	// This is done in the process phase so that attributes may be added by
	// modules or the theme during the preprocess phase.
	if (isset($variables['link_path'])) {
		// $variables['attributes_array'] contains attributes that should be applied
		// regardless of whether a link is being rendered or not.
		// $variables['link_attributes'] contains attributes that should only be
		// applied if a link is being rendered. Preprocess functions are encouraged
		// to use the former unless they want to add attributes on the link only.
		// If a link is being rendered, these need to be merged. Some attributes are
		// themselves arrays, so the merging needs to be recursive.
		$variables['link_options']['attributes'] = array_merge_recursive($variables['link_attributes'], $variables['attributes_array']);
	}
}
